Acoustic amplifier



FIG. 1 is a left, front, and top perspective view of an acoustic amplifier;

FIG. 2 is front elevational view thereof;

FIG. 3 is a rear elevational view thereof;

FIG. 4 is a top plan view thereof;

FIG. 5 is a bottom plan view thereof;

FIG. 6 is a left side elevational view thereof; and,

FIG. 7 is a right side elevational view thereof.

The broken lines shown in the drawings illustrate portions of the acoustic amplifier that form no part of the claimed design. 

CLAIM The ornamental design for an acoustic amplifier, as shown and described. 